Law Enforcement Case Study - Serious assault - Cell Site Analysis

The following is an anonymised case study based on a real assignment conducted by CCL-Forensics for a Law Enforcement Agency

Police were called to investigate an allegation of serious assault in a remote area.  The victim told investigators that during the attach, his attacker’s phone received a number of text messages.

Some time later police arrested a man answering the description of the attacker, but he claimed that he was several miles from the scene of the assault at the time.

The police force’s single point of contact (SPOC) obtained the suspect’s call data records from the phone network provider and called in CCL-Forensics’ cell site team.

One of our analysts carried out surveys of mobile phone signal strength at the scene of the attack and at the attacker's home, and compared the serving masts with that used by the suspect’s phone at the time of the attack.  The surveys were undertaken using both vehicle-mounted equipment, and hand-held surveying equipment due to the inaccessibility of the crime scene.

The survey results showed that the phone attributed to the suspect was using a mast which served the crime scene when the attack took place.  It also showed that particular mast was not capable of serving his home address where he claimed to have been.

In addition, a separate theoretical analysis was carried out to verify that the mast which served the crime scene could not have served the home address.  This was proven by the fact that the geographical terrain (hills and other obstructions) would not have allowed the serving cell to be detected at the home address.

When presented with this evidence, the suspect pleaded guilty – which avoided the need for a lengthy and costly trial.